Fleet marking applications are applications where a film having a pressure-sensitive adhesive on one side and some intelligent indicia on the opposed side is applied to sides of vehicles such as trucks or trailers, cabs, automobiles and the like. The sides of the vehicles, when the films are applied, may be riveted, seamed, sharply curved, corrugated and the like. The film, therefore, must be sufficiently flexible to conform to the irregularities without cracking or breaking. The pressure-sensitive adhesive must also be sufficiently aggressive to conform to irregular surfaces without separation or lifting.
Polyvinyl chloride films are typically used for fleet marking applications. The polyvinyl chloride film is printed with inks, normally "vinyl inks" by screen printing techniques and the like. They include metallic inks. It has been known to provide a protective top coat or clearcoat over the applied inks to be protective and, if desired, also decorative. The clearcoats have been based on aliphatic urethane diacrylate oligomers and phthalic acid ester plasticizer, used with or without the addition of polyvinyl pyrrolidone. Such compositions have been found to rapidly degrade upon exposure to natural light as indicated by a loss in gloss.